Manufacture of disazodyestuffs for dying and printing wool



Patented July 26, 1932 UNITED STATES PATENT OFFICE ADOLF KRELBSER, OF BASEL, SWITZERLAND, ASSIGNOR TO THE FIRM OF 3'. R. GEIGY S. A.,

OF BASEL, SWITZERLAND MANUFACTURE OF DISAZODYESTUFFS FOR DYING AND PRINTING WOOL No Drawing. Application filed August 30, 1930, Serial No. 479,093, and in Germany August 9, 1929.

I have made the surprising observation that new precious disazodyestufls result by combining tetrazo compounds of diaminodiphenylmethanedisulfonic acids and their 5 derivatives with two molecules of a naphtholmonosulphonic acid.

It could not be foreseen that dyestuffs of the type resulting from diaminodiphenylmethanedisulphonic acid and two molesules of a naphtholmonosulphonic acid, which thus contain four sulpho groups symmetrically distributed on the four nuclei, when dyed on wool, would surpass the corresponding dyestuffs unsulphonated in the diaminodiphenylmethane residue and which, contain only two sulpho groups (see German Patent No. 325,062), with respect to their fastness to light, that they show also a good fastness to fulling and a very good solidity to sulphur, that they leave cotton effects pure white and that they possess which is particularly importantexcellent properties for the direct printing on wool.

These dyestufis yield on wool, for example with oxalate of ammonia, fairly equalizing, covered prints of pure shade, of good fixation and fastness to water and ammonia and of remarkable fastness to light.

The following examples illustrate the invention:

Example 1 can ' tained according to this example has the fol- 34 kilos of '3 3-diamino-4 4-di1nethyldi-' filtered, The clear solution of the 3:8-diamino-4 4e-dimethyldiphenylmethane disulphonic acid is thentetrazotized in the usual way andcoupled with an aqueous solution of 70 kilos of 1 4-naphtholsulphonic acid and 60 kilos of soda. After some hours, the reaction mass is heated to 60 C. and the dyestuff is salted out, filtered and dried. The dyestuff constitutes a red powder; it dissolves in water with blue-red coloration, in concentrated sulphuric acid with red coloration and yields in dyeing and printing on wool a beautiful red shade with the good properties above stated. The dyestufi' 0b lowing formula SOaH SOsH SOzH S Ewample 2 34: kilos of 4 4-diamino-3 3'-dimethyldiphenylmethane are sulphonated as indicated in Example 1, see also B. Berichte 27, 1813 (1894:). The thus obtained 4:4-diamino-3.: 3'-dimethyldiphenylmethane disulphonic acid isgthen tetrazotized in the usual manner and coupled with kilos of 2: 6 naphtholsulph'onic acid and 60 kilos of soda. After the coupling being achieved, the reaction mass is heated to 60 C. and the dyestuff is salted out, filtered and dried. The dyestuficonstitutes a red powder and dissolves water with yello'w red and in concentrated sulphuric acid withblue-red coloration. It yields in dyeing and printing on wool fast orange tints; Thedyestuff obtained ac- 9o cording to this example has the following dyeing and printing on wool beautiful red formula: shades with good fastness to light, fulling,

soar soda N=N--oH2 N=N t 70 CH3 ('JH; (I S0|H SOaH sulphur, leaving cotton effects pure white and 7 being particularly adapted for direct prints on wool.

In witness whereof I have hereunto signed my name this 22nd day of August, 1930.

' ADOLF KREBSER.

Ewample 3 34 kilos of 4:4-diamino-2: 2-dimethyldiphenylmethane are dissolved at 7 0 C. in 130 kilos of sulphuric acid monohydrate and sulphonated at 10 C. with 110 kilos ofoleum of then stirred at C. until a test is easily and clearly soluble in water and soda solution. The 4: 4L-diamino-2 2-dimethyldiphenylmethane disulphonic acid, which separates out on diluting with 4 parts of water, or the sodium salt solution obtained with lime is then tetrazotized in the usual way and coupled with kilos of 1: a-naphtholsulphonic acid and 60 kilos of soda. After some hours, the dyestufi" is salted out, filtered and dried. It constitutes a red powder and is soluble in water with yellow-red and in concentrated sulphur acid with blue-red coloration. It yields in dyeing and printing on wool beautiful red tints. The dyestuff obtained according to this example has the following formula:

SOaH SOaH H ter and concentrated sulphuric acid with blue-red to red coloration and yielding in 

